[3dprinter-general] Remove charon.service

[Gregor Riepl]

Hi myon,

I have one more thing for you.

Upstream explained that the metadata service included with libCharon is 
not needed outside of Ultimaker hardware: 
https://github.com/Ultimaker/libCharon/issues/45#issuecomment-1619874104

I've pushed libcharon 5.0.0-4 to Salsa, which skips installation of the 
service file and drops the obsolete path patch.

It's not urgent, but please upload it when you have time.

Regards,
Gregor